Carbon back-bone

From MetallatedPhosphines. The synthesis of polymeric tertiary phosphines based on the reaction of lithium diphenylphosphide with chloromethylated polystyrenes continues to attract interest.9 10 Considerable breakdown of the carbon-carbon back-bone of PVC occurs on reaction with lithium diphenylphosphide in THF, and only oligomers of low molecular weight result.11 The potassium salt (9) reacts with chloromethylated polystyrene to form the polymeric diphosphine (10).12... 

A range of mixed-donor thia macrocycles have also been prepared using related techniques (5, 57, 58, 59, 60, 62, 63, 93,123,150, 213) water-soluble thioether macrocycles incorporating hydroxy-groups on the carbon back-bone have also been reported (163). 

For Nylon 6/6, if Ri is chosen as the methyl group attached to the carbon back-bone chain, then R2 must be the amide group and vice versa. 

Deslauriers, R., 1. C. P. Smith, and R. Walter Conformational flexibility of the Neurohypophyseal Hormones oxytocin and Lysine-Vasopressin. A Carbon-13-Spin-Lattice Relaxation Study of back-bone and side chain. J. Amer. Chem. Soc. 96, 2289 (1974). 

Figure 13. Mean square displacements of the sp carbons along the chain back-bone as a function of time for several temperatures for the CRC model and for T = 273 K for the FRC model.

The keypoint in this process for formation of anisotropic polymer carbon from polymer fibres with a C/C back bone which is preorientated in direction parallel with the fibre axis is the length constancy or even elongation of the polymer fibre during stabilization treatment by mechanical-means (34). This process parameter is the same as it has been applied for the not inflammable textile fibres (for instance black ORLON) before (35). Also today, stabilized PAN is used as a non inflammable textile. For this purpose minimum oxygen contents of 5-7 % are needed for inflammibility. 

In general, fragments characteristic of the PU back-bone, the Rj R2, and R3 groups, carbon clusters, and Ag clusters dominate the PU TOF-SIMS spectra in the low-mass range (m/z <400). 

Sepia. Cuttle-Fish bone. Calcareous substance found under the skin or the back of Sepia officinalis L., Cephalopoda. Habit. Mediterranean Sea, Atlantic and Pacific Oceans. Constit. Calcium carbonate and phosphate, gluten. 

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